Among balls roughly divided into solid balls and hollow balls, one known example of the hollow balls includes a bladder filled with compressed air, a reinforcing layer formed on the bladder by winding a nylon filament on the bladder in every circumferential direction, a rubber covering layer formed on the reinforcing layer, and a skin layer formed of a plurality of leather panels bonded to the rubber covering layer (see, e.g., Patent Document 1). The ball thus configured is called a bonded ball.
In another known example of the ball different from the above example, as disclosed by Patent Document 2, for example, edges of a plurality of leather panels are sewn together to form a spherical skin layer, and a bladder is contained in the skin layer. The ball thus configured is called a sewn ball.
Still another example of the ball is disclosed by, for example, Patent Document 3. In this example, a plurality of woven fabric pieces are sewn together to form a spherical woven fabric layer. A bladder is contained in the spherical woven fabric layer, and a plurality of leather panels are bonded to the surface of the woven fabric layer to form a skin layer.    [Patent Document 1] Specification of U.S. Pat. No. 4,333,648    [Patent Document 2] Published Japanese Patent Publication No. H09-19516    [Patent Document 3] Pamphlet of International Publication WO/2004/56424